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Coal. Coal is shiny black rock with energy. Coal was formed millions of years ago,. before the dinosaurs lived!. How Coal Was Formed. Back then much of the earth was covered in huge swamps. They were filled with giant ferns and plants.
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Coal Coal is shiny black rock with energy.
Coal was formed millions of years ago, before the dinosaurs lived!
Back then much of the earth was covered in huge swamps. They were filled with giant ferns and plants. As the plants died they sank to the bottom of the swamps.
Over the years, thick layers of plants were covered by dirt and water. • The plants were packed down by the weight of the dirt and the water. • After a long time, heat and pressure changed the plants into coal.
Coal is a Fossil Fuel • Coal is called a fossil fuel because it was made from plants that were once alive. • The energy in coal came from the sun.
Most Coal is Buried Underground. Rocks and Dirt Coal
So how do we get coal? We mine it!
If coal is near the surface, miners dig it up with a huge machine. • First, they scrape off the dirt and rock. • 2. Then they dig out the coal. This is called surface mining.
After the Coal is Mined: The land is made usable again! The dirt and rocks are put back. Trees and grass are planted. This is called reclamation.
If the coal is deep in the ground, tunnels called mine shafts are dug down to the coal.
Some mine shafts are 1,000 feet deep! Machines dig the coal and carry it to the surface. This is called deep mining.
So how does coal go from This… ? to this…
First, coal is transported. • Most coal is moved by trains to power plants and factories. • The cost of shipping coal can cost more than it costs to mine it!
Coal is burned in a large furnace to heat water to make steam. Steam pushes the blades of a turbine. The turbine is connected to a generator, which makes electricity.
How Coal turns into Electricity 1. Coal is burned, which produces steam. 2. Steam turns a turbine. 3. The turbine generates electricity. 4. Power lines carry the electricity to our homes.
Coal is one of our most important energy sources! Most of the coal mined in the United States today is used to make electricity.
Coal is one of our most important energy sources! In 2003, more than half (51%) of the country's 3.9 trillion kilowatt-hours of electricity used coal as its source of energy.
Coal is also used in steel and iron production. 64% of steel production worldwide comes from iron made in blast furnaces that use coal!
Coal Production Coal is mined in 27 states. Wyoming produces the most coal.
Coal Reserves • Coal reserves are beds of coal still in the ground waiting to be mined. • The United States has the world’s largest known coal reserves!
However, eventually we will run out of coal! • If we continue to use coal at the rate we use it today, we will have enough coal to last almost 300 years.
Coal is Non-Renewable The coal we use today took millions of years to form. We can’t make more in a short time. That is why it is called non-renewable.
Burning coal can cause pollution. Burning coal produces emissions that can pollute the air.
Burning coal can cause pollution. Burning coal also produces carbon dioxide, a greenhouse gas.
Acid Rain • When coal is burned, a chemical called sulfur may also be released. • Sulfur mixes with oxygen to form sulfur dioxide. • Sulfur dioxide is a chemical that can affect trees and water when it combines with moisture to produce acid rain.
Power plants and factories work hard to keep pollution from getting into the air. • They clean the coal before they burn it. • They use scrubbers to clean the smoke before it goes into the air.
Discussion Questions • Why do you think the United States continues to rely so much on coal as our primary energy source, even though we know it pollutes the environment? • What do you think we will use for energy once we run out of coal?
